GitLab

Avoiding unnecessary complexity in FrameSinkObserver. We are interested
in events like creating and destroying FrameSinks which are handled in
"OnCreated...FrameSink" and "OnDestroyed...FrameSink", so we don't need
to use events "OnRegistered...Support" and "OnUnregistered...Support".
These two just give us the unnecessary overhead of handling more events.

Sorry for missing this in previous CL.

Bug: 816802
Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel
Change-Id: I53eba6a103834cc9d48ced14e013825c3b49027a
Reviewed-on: https://chromium-review.googlesource.com/978374
Commit-Queue: Illia Martyniuk <illiam@google.com>
Reviewed-by: kylechar <kylechar@chromium.org>
Cr-Commit-Position: refs/heads/master@{#545776}